Circuit breaker



F. L. GELZHEISER El" AL Oct. 20, 1953 CIRCUIT BREAKER Filed Sept. 11 1951 Fig.|.

ATTORNEY Patented Oct. 20, 1953 CIRCUIT BREAKEB Francis L. Gelzheiser, Pittsburgh, and Joseph A. Dmbney, Beamer, Pa., assisnors. t9 Westingf .lipase Electric aorpration, East Pittsburgh, P .a corporation of Pennsylvania Application iSeptember 11, 195'1.1Serial-No. 246,082

12 Claims.. 1

This invention melates to circuit 'breakers and more :particularly to circuit lbreakers which are manually operable .to open and. yclose the circuit and which are automaticallyoperated Yto open the circuit -fin response sto .overload currents.

An .object .of the invention is to provide a .cir. cuit breaker which is manually operable to open and yclose the circuit and automatically operated in .response #to Aoverload currents to open the circuit, 4with .novel means for .gi-ving an indication that the breaker :has been automatically opened.

Another .object of .the invention is to 'provide a. biscuit breaker having Aswitch means `that is operated .only in Imosponse to automatic Iopening of the `breaker Ato `effect fan indication of the-condition ,of :the ibreaker.

.another .object of .the invention lis to :provide a .circuit breaker *with means of simple construction and Vreliable in `operation tor .signalling when theroirouit breaker has `been.autoxnatieally tripped open.

The no-.vel :features lthat are `consideredchar.- aoterstic .of 'the invention .are set lforth in paroticular in the appended claims. The invention itself, however, (both .as .to .structure and operation, together awith additional obj ects and vadventtages thereof will be best understood from the following .detailed `description thereof rwhen vread in lccnftiunetion with accompanying drawing.

.In said rdrawing:

Figline l .1e verticaal `sectiimal aview :of .a ocirouit breaker embodying the .principles .of the invacation.

:Eig I2 is an :enlarged horizontal sectional avlew tnkcmsubstantazlly .on IiITHof zEig. al showing the .Signal switch and the operating means tbercfqor.

,Ha isrfventicalzend view .of the tbreakerwith the .cover politi-y :broken away to more .clearly iik-limitate the .signal .switch vand :the operating means therefor. RQEIr-ingf'i@ gFig. ..1 .of :the drawing, the circuit breaker .illustrated comprises, .in general, Aa. nous.. ing-.comprising a recessed .base :Ill of molded Suliiilg miiieriahanda .Cooper-.ating cover .1:3 also of molded 'insulating material, .a Asi:ationarv .com tact gli., LB pvoted ,switch memberfl'll .oarryilaxgol mollahl @moet L9 :for .cooperating with the asta.. tionnry Contact, .operating means yindicated xeen.- ilvilly -fa-.t r..2;l and .a trip ldevioe indicated .generally 83h21.

-l'h Slannry contact A55 iis -,mounted on the .endet a conduotingstrip 25 `.which extends outwardly brauchen openinein :the base :n and has connecting 'means .27 on :its cuter end.

LThe .operating .mechanism 12.4 and :the lpivoted switch member l1 yare supponted in a Urshaped main frame .29 suitably secured to the base M.-

Ihefswiteh member H, which .carries the moyable contact I9, comprises a resilient stripsecixred at its .other ,end .to a ysupport member .3| pivotatly mounted on .a pin .33 .supported in .the ,side members .of the main frame 2Q..

The operating .meehanisml for :the ...circuit bren-.ker .comprises fa toggle consisting .of a pair of .toggle links .35 .and :331, -a apivoted carrier :39, en oyercenter .spring AI and .a U :shaped oper-'.- ating lever .43. .The toggle 3:5 and .3:1 .mae pivotally .connected by la vknee :pin A5 `and ythe toggle link `.3;5 :is pivotally connected to the car..- rier 3;9 iby a ,pi-512011 .pin .411. 'The toggle link :31 is pivotal-ly connected by vIneansof .a pivot pin 4,9 to the support member 3 l. The overcenter spring 4d is .connected at its ,lower .end to ythe knee .pivot Din Lof Ytbe toggle 1315-.-.331 .and .at its outer end to :the :yoke portion of. the l.Ueshaned .operating lever .43. 'lll-he legs .o f rthe :operating 'lever .43 are pivoted on @rejections rtl A-'.fo.rx.1.1edontw..erdlv from .the sides of @the .mein frame 29,. Ears 5.3 .formed outwardly from .the .main frame .2.9 serve .torlimit .the movement of the ,operetingflever .4.3.- .Annee eratine handle 55 of moldedfinsuletingmarialis mounted :9.1.1 the outer end .of the operating :leser 4.3 andfnroieets rough .en opening 5I 1in tbe cover -I 3. ,arcuate portion 5.9 pf .the handle serves t9 substantially close the opening 51 in all positions .of the .operating .lever .43..

51.11 .carrier-.3911s pivotally amounted ons pivot pill 1.54 .SupPQrQd 11.1 nthe l,main frame v219 .andas n .ally .releesebly restrained fin .operative-positien by .the trip .deyicezl 'The circuit breaker .is .opened manually by countenclgokwis@ .mtementof the handle 5 and the :opeletins .lever 4.3 which vcarries the line .of action of the .oveneenter Ysprings Al .over to .the lett of the pivot min ..41. vThis action causes cob lame of the toggle .3i-31 fandonenngimovement of thetstiitch member .111. Clockwise .moyement of it e handle 5.5 .and .the Yoperating `.lever At rback t0 the :DQsition shown .moves the line .of action ,of thelovercenter .springs 4| .across .to the right; .of the :pivot vpin il :whereupon the toggle 3&5-31 fis straightened and the switch member 4'1 -is actuated :to close .thecontacts The `trip device P25 Lcomprises Va -bmetal velement -63 moving an 4armature :65 mountedthereon and a xed magnetic imember 61. The bimetal element 63 .and the magnetic lmember 161 have mounting :feet Lformed thereon vand are rigidly secured f-to the ibase :H by means `of Lafscrew A1659; One

end of the bimetal element 93 is connected by means of a ilexible conductor 1I to the switch member I1 and the other end of the bimetal element 63 is connected by means of a exible conductor 13 to a conducting strip 15 which extends outwardly through an opening in the end wall of the base II and has a terminal connecting means 11 mounted on its outer end. An adjusting screw 19 threaded into the upper end of the bimetal element 63 has a latch portion 8| which is engaged by a latch member 93 on the carrier 39, in order to releasably restrain the carrier in operative position.

When an overload current below a predetermined value of, for instance, ten times normal rated current occurs the bimetal element 53 becomes heated, and when heated, a predetermined amount bends toward the left releasing the carrier 39. When released the carrier 39 rotates clockwise about its pivot 6I under the influence of the overcenter springs 4I and carries the pivot 41 across to the right of the line of action of the overcenter springs. This causes collapse of the toggle 35-31 and opening movement of the switch member I1.

Following an automatic opening operation, the carrier 39 is reset and relatched by movement of the handle 55 t0 the o' position. During this movement a projection 85 on the operating lever 43 engages and moves the carrier 39 counterclockwise. This movement causes the latch meinber 83 to wipe by the latch 8| slightly7 iexing the bimetal 63 which thereafter resumes its normal position with the latch 8| in latching engagement with the latch member 83. The circuit breaker is then closed in the previously described manner by movement of the handle 55 to the on position.

Upon the occurrence of an overload current of ten times or more of normal rated current or a short circuit current, the electroresponsive means 65-61 is energized suiciently 'by the current owing through the bimetal element 53 and moves the armature 55 toward the fixed magnetic member 61 bending the bimetal element and causing instantaneous release of the carrier 39 and opening of the breaker.

Means is provided for efecting a signal when the circuit breaker is automatically tripped open. The signalling means, indicated generally at 81 (Fig. 2), is not operated when the breaker is manually opened. The signal means is enclosed in a separate casing 85 of insulating material and comprises a stationary contact mounted on a conducting strip 93 and a cooperating movable contact 95 mounted on a resilient switch arm 91. The conducting strip 93 is secured to the casing 89 by a rivet 99 which also secures a terminal I0| to the outside of the housing. One end of the resilient switch arm 91 is secured to the casing 30 by a rivet |03 and this rivet also secures a terminal to the outside of the casing 89. The bias of the resilient arm 91 is such so as to bias the contact 95 closed against contact 9|. The terminals IOI and |95 serve to connect the signal switch in an electric circuit to energize a signalling device (not shown) which may be either a visible or audible device. The signal switch casing 89 is removably mounted on the outside of the cover I3 of the circuit breaker by means of a strip |01, the ends of which are removably fastened to the cover by screws |09 (Fig. 3) which are threaded into the cover I3.

The signal switch contacts 9 I-95 are normally held in open position against their bias by means of an actuating spring III. The spring III has a portion II3 extending at right angles (Fig. 1) to the main body of the spring by which the actuating spring is mounted on the inside surface of the cover I3 and secured thereto by screws II5 and nuts IIT. The spring III also has an actuating portion II9 formed substantially at right angles to the main portion III and extending transversely across the breaker operating mechanism adjacent the carrier 39 to be actuated by the carrier.

Disposed between the main body of the spring III and the resilient switch arm 91 of the signal switch is a pair of plungers I2I and |23. The plunger I2I extends through an opening in the cover I3 and has a ange |25 thereon which is disposed in a counterbore in the outside of the cover I3. The plunger |23 extends through an opening in the wall of the casing 89 adjacent the cover I3 and is disposed between the plunger I2I and the resilient switch arm 91. The flange |25 cooperates with the cover I3 of the circuit breaker and with the casing 89 of the signal switch to form a tortuous path substantially preventing the passage of hot gases from the interior of the circuit breaker to the interior of the signal switch.

The actuator spring III is stronger than the resilient switch arm 91 and its initial tension is sufcient to normally maintain the resilient switch arm 91 in the open position through the agency of the plungers |2I and |23. In the closed position of the breaker the parts are in the positions shown in full lines in Figs. 1 and 2. When the circiut breaker is tripped open in response to an overload current and the carrier 39 rotates in a clockwise direction (Fig. l) to eiect opening of the breaker contacts, a surface |21 on the carrier 39 engages the portion II9 of the actuating spring III and bends the spring III to substantially the position shown by dot and dash lines at IISa (Fig. 2). This further stresses the spring and moves the main body I I thereof away from the plunger I2| whereupon the tension of the resilient switch arm 91 acts to close the signal switch contacts ill-95 and effect energization of the signal circuit.

When the carrier 39 is rotated counterclockwise by manipulation of the handle to reset the mechanism, as previously described, the surface |21 moves away from the portion I9 of the spring IiI and the resilience of the spring III causes it to resume its normal position. At this time the spring III acts through the plungers I2I-|23 to overcome the tension of the resilient switch arm 91 and open the signal switch contacts 9|-95.

The signal switch is not operated on manual opening of the circuit breaker since on such operations the carrier 39 is not released, hence, the signal switch functions to give a signal only on automatic opening of the breaker.

It is a very desirable feature of the invention that both the switch unit 81 and the actuating spring III are mounted solely on the cover I3 of the breaker. This is important from a manufacturing standpoint since no modification of the breaker mechanism or of the base II is required, it only being necessary to mount on the base II carrying the breaker mechanism, a cover I3 having the switch unit 81 and the actuating spring thereon. After the cover I3 is mounted on the base I I, the housing is sealed in a well known manner to prevent tampering with the breaker.

It will be seen that the invention provides a circuit breaker having a signal switch that is esame@ `operatedfby fthebr'eaker mechanism-'only on automatic 'tripping operations. The signal switch -is of simple construction i-having few parts, zis :reliable in operation and inexpensive Tte manufacture. 'The signal :switch l'itself 2is removably mounted yon theoutside of th'e breaker housing to permitfremovalfand replacement thereof withiout disturbing the seal of the breaker housing and-without disturbing the calibration of thecir- "cuit breaker.

While the invention has :disclosed fin accordance with rthe lprovisionsfo the lpatent `stat-- utes, lit is 'to -'be `understood .that -various changes fand modications fmay be-made in -the structural `details .and combination fof elements disclosed without `"departing -iromfsome of the essential features of the invention.

We claim vas our invention:

Y1. A circuit breaker comprising anenclosing housing, operating fmeans =releas`a`ble fto cause automatic openinglo'f.saidibreaker anditripmeans responsive -to overload currents for eiecting release of -saidreleasable operating means and automatic opening of said breaker, auxiliary switch means y:mounted on'theioutside of said-enclosing housing, and actuatingmeansior said auxiliary switch means mounted on the inside o'f said housing and-engageable by said :releasable operating means to effect operation-v of said auxiliary switch conditions for releasing said releasable means, an o auxiliary switch device removably mounted on the outside of said housing, actuating means for said auxiliary switch device mounted on the inside of said housing and normally maintaining said auxiliary switch device in operative condition, and said actuating means being engaged by said releasable means and moved to a position to permit operation of said auxiliary switch device.

3. In a circuit breaker comprising a housing, a releasable member operable when released to effect automatic opening of said circuit breaker, trip means for effecting release of said releasable member, auxiliary switch means mounted on the outside of said housing, biasing means biasing said auxiliary switch means to an operative position. actuating means for said auxiliary switch means comprising a spring mounted on the inside of said housing normally engaging and holding said auxiliary switch means against the bias of said biasing means, and said actuating spring being engaged by said releasable member upon release thereof and moved to a position to permit said biasing means to operate said auxiliary switch means.

4. A circuit breaker comprising a housing, means releasable to cause automatic opening of said circuit breaker, trip means for eiecting release of said releasable means in response to abnormal circuit conditions, an auxiliary switch mounted in said housing, biasing means normally biasing said auxiliary switch to an operative position, actuating means for said auxiliary switch normally restraining said auxiliary switch against the bias of said biasing means, and said actuating means being engaged by said releasable means upon release thereof and moved to a position to permit said biasing means to actuate said auxiliary switch.

5. A circuit breaker comprising a housing, means releasable to cause automatic opening of 'said breaker, tmipim'eans for leffectingrelease-o! 'said :releasable means in response to abnormal circuit conditions, an auxiliary `'switch mounted on said housing', biasing means ,normally ibiasing said auxiliary switchito angoperative position, actuating 'means for Asairazl auxiliary switchcomprising 1a biased .member mounted on said :housing normally restraining said auxiliary switch against ltl-ie ibia's of `lsaid :biasing means, and said actuating means beingfengaged by said relmisasble .means upon release lthereof :and moved Jag-einst its lbias Ito ya ypositionito permitfsaidf-biasing ltofactuateisa'id auxiliary switch.

6. .A circuit 'breaker comprising a l housing of imolded insulating material, fa releasable mem- :ber zoperable when released :to effect automatic 'opening of said breaker, trip :means for -eiec'ting .release of said Lreleasable member, an auxiliary .comprising La casing vmountedon `said v"heirs-- ing, separable v:contact 4in Lsaid casing Lbiased closed, actuating 4means tor-said auxiliarylswi'tch amounted `on said housing and normally Aholding -said --separa'ble contacts open, said releasable member when released engaging-andmovingfsaid actuating ymeans f'to permit said `separable contorclose.

'51. JA fcircuit breaker comprising a lhousing of :molded insulating material, -a--releasable lmember operable when released vrto effect automatic ropen-- ing of :said breaker, trip means for effectingre- `lease of :said .releasable member, an auxiliary switch comprising a casing removably mounted on said housing, separable contacts in said 4casing biased closed, actuating means for said auxiliary switch comprising a spring mounted on said housing and normally holding said separable contacts open, said releasable member when released engaging and moving said actuating means to permit said separable contacts to close.

8. A circuit breaker comprising a housing of molded insulating material, operating means comprising a member releasable to effect automatic opening of said breaker, trip means responsive to overload circuits for releasing said releasable member, a manual lever for opening and closing said breaker and operable to reset said releasable members, an auxiliary switch comprising a casing mounted on `said housing, auxiliary contacts in said casing, a resilient switch member in said casing biasing said auxiliary -contacts to closed position, actuating means for said resilient switch member comprising -a spring normally holding said resilient switch member in open position, said releasable member when released engaging and moving said actuating means to permit said resilient switch member to close said auxiliary contacts, and said actuating means upon resetting of said releasable member moving said resilient switch member to open said auxiliary contacts.

9. A circuit breaker comprising a housing of molded insulating material, operating means comprising a member releasable to effect automatic opening of said breaker, trip means responsive to overload Icircuits for releasing said releasable member, a manual lever for opening and closing said breaker and operable to reset said releasable member, an auxiliary switch comprising a casing removably mounted on the outside of said housing, auxiliary contacts in said casing, a resilient switch member in said casing biasing said auxiliary contacts to closed position, actuating means for said resilient switch member comprising `a spring mounted on the inside of said housing and normally holding said resilient switch member in open position, said releasable member when released engaging and moving said actuating means to permit said resilient switch member to close said auxiliary co-ntacts, and said actuating means upon resetting of said releasable member moving said resilient switch member to open said auxiliary contacts.

10. A circuit breaker comprising means releasable to eiect automatic opening of said breaker, trip means for releasing said releasable means, means for resetting said releasable means, auxiliary contact means comprising a resilient switch member biasing said auxiliary contact means to closed position, an actuator for said resilient switch member comprising a spring stronger than said resilient switch member disposed to normally hold said resilient switch member in open position, said releasa-ble means when released engaging and moving said spring to permit said resilient switch member to close said auxiliary contacts, and said spring moving said resilient switch member to open position when said releasable member is reset.

11. A circuit breaker comprising :an enclosing housing including a base and cover, operating means releasable to cause automatic opening of said breaker and trip means responsive to overload currents for effecting release of said releasable operating means and automatic opening of said breaker, all mounted on said base, auxiliary switch means mounted on the outside of the cover portion only of said enclosing housing, and actuating means for said auxiliary switch means mounted on the inside of the cover portion only of said housing and engage- 4able by said releasable operating means to effect operation of said auxiliary switch means.

12. A circuit breaker comprising a housing including a base and cover of molded insulating material, a releasable member operable when released to effect automatic opening of said breaker, trip means for effecting release of said releasable member, an auxiliary switch comprising a casing mounted solely on the cover portion of said housing, separable contacts in said casing biased closed, actuating means for said auxiliary switch mounted solely on the cover portion of said housing and normally holding said separable contacts open, said releasable member when released engaging and moving said actuating means to permit said separable contacts to close.

FRANCIS L. GELZHEISER. JOSEPH A. DROBNEY.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,485,580 Zimmerman Mar. 4, 1924 2,276,365 Barrett Mar. 17, 1942 2,507,949 Asdor May 16, 1950 

